As The Associated Press writes, "the two sides have been engaged in intense clashes since the unrest began on Saturday with protesters trying to force out the generals who have failed to stabilize the country, salvage the economy or bring democracy more than nine months after taking the reins from former President Hosni Mubarak."

Today's gathering, NPR's Soraya Sarhaddi Nelson reports from the scene, appears to be the largest since the Arab Spring protests back in January and February. Organizers are calling today's protest a "million man march." She's seeing clouds of tear gas rising above the square. And there are already reports of injuries.

There is one key difference between what's happening now and what happened earlier this year, though, Soraya adds. "Outside of the square and the side streets, life is continuing," she says. "There are people who are going to work and going about their daily business only a few hundred feet from where this is playing out." There is no curfew in the city.

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